ARM: SPEAr13xx: Fix Interrupt bindings

   - Correct interrupt bindings for uart, ethernet and pmu.
   - Added interrupt binding for keyboard.

Signed-off-by: Vipul Kumar Samar <vipulkumar.samar@st.com>
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>